JPH057725B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel attitude control method for controlling the attitude of an unmanned vehicle with respect to a target object to a desired attitude. By installing reflectors on targets such as
It is an object of the present invention to provide a method for controlling the attitude of an unmanned vehicle, which can freely and easily control the attitude of the unmanned vehicle, such as the direction in which it approaches a target object.

An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, reference numeral 1 denotes an unmanned vehicle of an unmanned vehicle system that does not have a guide track, and a left drive wheel 3L and a right drive wheel are respectively driven by motors 2L and 2R. 3R is provided at the center of the front and rear of the vehicle body, and encoders 4L and 4R are coupled to respective axles of both drive wheels 3L and 3R. The output pulses of the encoders 4L and 4R are input to the left drive wheel rotation amount detection section 5L and the right drive wheel rotation amount detection section 5R, respectively, and the outputs of the rotation amount detection sections 5L and 5R are supplied to the calculation control section 6. Ru. The unmanned vehicle 1 is
In the arithmetic control section 6, rotation amount detection sections 5L, 5R
This is an unmanned vehicle that does not have a guide track and runs while comparing and calculating the actual travel distance data inputted from the central control room with the set distance data given from the central control room etc., and the calculation results are as follows. The power is applied to the motors 2L and 2R through the drive section 7L for the left drive wheel and the drive section 7R for the right drive wheel, respectively. In this embodiment, a description of this travel control of the unmanned vehicle 1 will be omitted. Reference numeral 8 indicates a target object such as a moving device placed in the yard of the unmanned driving system. 1A,
1B are a light emitting element and a light receiving element, respectively,
It is attached so that the center is located on the vertical axis Z passing through the vehicle center axis X on the vertical front surface of the unmanned vehicle 1, and the center axis X of the vehicle is located on the light reflector 8A.
When the light receiving element 1 is oriented perpendicularly to the opposite slope of
The amount of light received by B is the maximum. The light reflector 8A is attached to one vertical surface of the target object, for example, the transfer device 8.

The light emitting element 1A receives a constant level output modulated at a specific frequency from the light emitting element power supply section 9, and projects modulated light. The output of the light receiving element 1B is input to the detection amplification section 10. The detection amplification unit 10 receives an electrical signal at a level proportional to the amount of incident light from the light receiving element 1B, and demodulates it at the above-mentioned specific frequency. Therefore, of the light projected onto the light reflector 8A from the light emitting element 1A, an electrical signal with a level proportional to the amount of light reflected by the light reflector 8A is output. This output characteristic is shown in FIG. The angle α is the angle that the central axis X makes with the light reflector 8A. Reference numeral 11 denotes a peak detection section, which detects when the output of the detection amplification section 10 reaches the maximum value and supplies a peak detection signal P to the calculation control section 6. The calculation control unit 6 is
In addition to the travel control function, it has a function of outputting a fixed point turning scan command S when the unmanned vehicle 1 finishes turning to an initial guidance position, which will be described later, to cause the unmanned vehicle 1 to perform a fixed point turning operation. Fixed point rotation scan command S
is a command for rotating the driving wheels 3L, 3R in opposite directions, and the content thereof is the rotational direction of each driving wheel 3L, 3R that is predetermined corresponding to the above-mentioned initial guidance position. , 7R to the motors 2L and 2R individually. When the fixed point turning scan command S is output, the unmanned vehicle 1 sets the turning center O to the intermediate point between the drive wheels 3L and 3R.
Turn at a fixed point. This fixed point rotation scanning command S disappears when the calculation control section 6 receives the peak detection signal P. At the same time, the calculation control section 6 controls the rotation amount detection section 5.
A clear signal is sent to L and 5R, and thereafter the drive wheels 3L and 3R are inputted from the rotation amount detection parts 5L and 5R.
The presence or absence of an over-turning angle is detected from the difference in the amount of rotation, and if over-turning occurs, an over-turning correction command Sf is output. The over-turn correction command Sf adjusts the drive wheels 3 necessary to make the unmanned vehicle 1 turn at a fixed point only at the over-turn angle.
The contents include the amount and direction of rotation of L and 3R, and are applied to motors 2L and 2R through motor drive units 7L and 7R. Note that the rotation direction of the drive wheels 3L and 3R in this case is opposite to the rotation direction when the fixed point turning scan command is issued.

Next, an explanation will be given of an unmanned vehicle system in which the operation of this embodiment is applied to the target object 8 production method shown in FIG.

The unmanned driving system consists of a linear main route where the automated warehouse Y is located and a plurality of branch routes where there are targets 8 such as transfer devices. After loading objects, the vehicle then receives a command to specify the target object 8 as the destination, and travels to the initial guidance position Po (Poa, Pob, Poc) corresponding to the target object 8 as the destination. The main path between the starting position Ps of the unmanned vehicle 1 and each initial guidance position is a straight line except for the portion required for turning the unmanned vehicle 1, and The unmanned vehicle 1 is positioned at the target position by comparing the number of output pulses and the distance to the initial guidance position Poa given in advance. If the unmanned vehicle 1 slightly deviates from the above-mentioned straight line in a turning manner, the deviation is detected by a gyro compass (not shown), and the angle to be corrected is supplied from the calculation control unit 6 to the motors 2L and 2R. This will cause automatic correction. When turning to the initial guidance position, set the turning angle in advance (90° in the figure)
is set in advance, and a comparison calculation is made between this set angle and a value based on the output of the gyro compass. The direction of the unmanned vehicle 1 is changed to a branch route branched at a predetermined angle from the main route, and the attitude of the unmanned vehicle 1 after turning and stopping is as shown in FIG.
Suppose that it is shifted by an angle θ. When the unmanned vehicle 1 stops, the calculation control unit 6 outputs a fixed point turning scan command S. The direction of deviation of the unmanned vehicle 1 with respect to the center axis X is predetermined by the turning direction of the unmanned vehicle 1 toward the initial guidance position Poa, and in this case, it is shifted to the left. Therefore, the fixed point turning scan command S commands a right turn and is applied to the motors 2L, 2R through the motor drive units 7L, 7R, respectively, and the unmanned vehicle 1 starts a fixed point turn to the right. This fixed point turning continues until the calculation control section 6 receives the peak detection signal P from the peak detection section 11. Central axis X of unmanned vehicle 1
However, as shown by the solid line in FIG. 4, when the unmanned vehicle 1 turns to a position perpendicular to the light reflector 8A and the peak detection signal P is output, the turning scan command from the arithmetic control unit 6 is S disappears. When the unmanned vehicle 1 turns excessively, the arithmetic control unit 6 issues the following information:
Since the excessive turning correction command Sf is output, unmanned vehicle 1
The vehicle makes a fixed point turn in the opposite direction to the above fixed point turning direction by the amount of overturning, and takes a posture in which the traveling vehicle center axis X faces perpendicularly to the reflective surface of the light reflector 8A.

FIG. 6 shows another embodiment of the present invention, in which a light emitting element 1A and a light receiving element 1B are attached to, for example, the same panel to constitute a scanning section 12, and this scanning section is mounted on the unmanned vehicle 1. It is provided so as to be able to turn, and is driven to turn by a scanning motor 13. A rotation scanning command M having a predetermined rotation direction corresponding to the initial guidance position is applied to the motor 13 from the arithmetic control section 6 through the scanning motor drive section 14. Reference numeral 15 denotes a direction detection unit that detects the turning angle θ of the scanning unit 12 with respect to the vehicle center axis X from the rotational speed of the motor 13, and inputs the detected turning angle θ to the calculation control unit 6. This turning angle θ is an angle between the vehicle center axis X of the unmanned vehicle 1 and the light reflector center axis Y. Arithmetic control unit 6
calculates the amount of rotation of the driving wheels 3L, 3R necessary for the unmanned vehicle 1 to turn at a fixed point by the input turning angle θ based on the input turning angle θ, and calculates the calculated rotation of the driving wheels 3L3R. The fixed point turning command N containing the amount and each rotation direction is sent to the drive units 7L and 7R.
, to the motors 2L and 2R, respectively. The rotation scanning command M disappears when the peak detection signal P is sent out from the peak detection section 11.

In this embodiment, when the unmanned vehicle 1 stops at the initial guidance position, the arithmetic control unit 6 outputs a turning scanning command M, the scanning unit 12 starts turning, and the turning movement is detected by the peak detection signal P. Continue until output. When the peak detection signal P is output, a fixed point turning command N is outputted from the calculation control unit 6, and the unmanned vehicle 1 turns at a fixed point in the turning direction of the scanning unit 12, and the central axis X of the traveling vehicle reflects light. It stops when it turns until it assumes a posture perpendicular to the reflective surface of the body 8A.

In each of the above embodiments, if a microcomputer or the like is used as the arithmetic control section 6, the peak detection process of the peak detection section 11 can be performed by software, and the motor 13 for driving the scanning section 12 can be used. If a pulse motor is used, the scanning unit 1 can be controlled by counting the number of pulses that drive the motor.
The direction detection unit 15 can detect two directions.
The peak detection section 11 becomes unnecessary. Furthermore, the light emitting element 1A and the light receiving element 1B may be arranged on the wheel shaft.

As described above, according to the present invention, since the attitude of an unmanned vehicle is controlled with respect to a reflector attached to a target object, there is no need to provide a guide under or on the road surface, and This has the effect of being extremely flexible in dealing with changes in travel routes or changes in the installation positions of targets.

[Brief explanation of the drawing]

FIGS. 1A and 1B are a side view and a plan view, respectively, of an unmanned vehicle that has implemented the attitude control method for an unmanned vehicle according to the present invention, and FIG. 2 shows the attitude of an unmanned vehicle that has implemented the above attitude control method. FIG. 3 is a schematic diagram of an unmanned vehicle system to which the present invention is applied; FIG. 4 is an explanatory diagram of the operation of the embodiment of FIG. 2; and FIG. 5 is a block diagram of an embodiment of the control method device. FIG. 6, which shows the output characteristics of the detection amplification section in this embodiment, is a block diagram of another embodiment of the present invention. In the figure, 1... unmanned vehicle, 1A... light emitting element, 1B... light receiving element, 2L, 2R... motor, 3A, 3B... driven wheel, 3L, 3R... driving wheel, 4L, 4R... Encoder, 5L, 5R...
Rotation amount detection section, 6... Arithmetic control section, 7L, 7R...
...Motor drive unit, 8...Target, 8A...Light reflector, 10...Detection amplification unit, 11...Peak detection unit, 12...Scanning unit, 13...Motor, 14...
Motor drive unit, 15...direction detection unit, X...travel center axis.

Claims (1)

[Scope of Claims] 1. When controlling an unmanned vehicle to travel toward a target provided on each of a plurality of branch routes branched at a predetermined angle with respect to a straight main route, the unmanned vehicle This system controls the attitude toward a target when turning from a route to a branch route to an initial guidance position, and the unmanned vehicle is provided with a pair of light emitting element and light receiving element, and the unmanned vehicle is provided with a pair of light emitting element and light receiving element, A light reflector that reflects the projected light is disposed on the target object, and the unmanned vehicle is provided with a light reflector that reflects the projected light, and when the unmanned vehicle finishes turning to the initial guidance position, the left and right drive wheels of the unmanned vehicle are An arithmetic control unit is provided that issues a fixed point turning scan command including a rotational direction, and the unmanned vehicle issues the fixed point turning scan command until the light receiving element assumes a posture in which it receives a maximum amount of light from the light reflector. A method for controlling the attitude of an unmanned vehicle, comprising: causing the vehicle to turn at a fixed point in the vicinity of the target object. 2. The attitude control method for an unmanned vehicle according to claim 1, wherein two sets of a light emitting element and a light receiving element are integrally attached to the unmanned vehicle. 3. A pair of a light emitting element and a light receiving element are provided so as to be able to turn with respect to the unmanned vehicle, and the light emitting element and the light receiving element are turned to a direction in which the light receiving element receives the maximum amount of light from the light reflector. 2. The method of controlling the attitude of an unmanned vehicle according to claim 1, wherein the unmanned vehicle is rotated at a fixed point until the center axis of the vehicle coincides with this direction.